Revealing mistake: Batman drives out of the batcave alone. The first bit of stock footage of the car leaving the cave does indeed show him alone in the batmobile. But the very next stock shot of the car speeding down the dirt road shows us Robin sitting in the passenger seat. (00:05:25)
Audio problem: As Susie deposits a dime in the coffee machine, the camera starts to pan down towards the opening where the cup will appear. You hear the cup then the quarters fall, but you can see the cup full of quarters is already in place before the sound is made.